Percussion fuse



M y 1939. P. E. J. DENOIX 2,156,471

PERCUSSION FUSE :Filed March 29, 1938 3 Shets-Sheet 1 I2 2 f f [3 206 L 4 -7 8 I I i 4 784 May 2, 1939.

P. E. J. DENOIX PERCUSSION FUSE Filed. March 29, 1938 3 Sheets-Sheet s Patented May 2, 1939 P TENT il'ji PERCUSSION FUSE.

Application March 29, 1938, Serial No. 198,761 In Luxemburg April 2, 1937 2 Claims.

This invention relates to a percussion fuse adapted to be employed especially for priming aerial bombs and similar projectiles.

An object of the present invention is to provide a fuse wherein the member, the displacement of which determines the arming of the fuse, is held by a cross-piece or equivalent member of a tube locked in the safety position by balls or other locking devices against which it is maintained in contact by a spring, the other end of which acts on a spindle having a neck portion, in such a manner that said spindle tends to bring its neck opposite the balls, in order to enable them to withdraw into the interior thereof, with a View to permitting the sliding of the tube, which effects the arming of the fuse, while the displacement of the spindle is nevertheless prevented up to the moment of release by means of an auxiliary locking member adapted to be discarded.

According to a further feature of the invention, the auxiliary locking member comprises a lever having two limbs which bear with tight friction against flats on the necked spindle.

Still a further feature of the invention consists in that the limbs of the lever are connected with the spindle in such a manner as to be able to detach themselves therefrom under the action of a determined tensile stress, said lever having cams which cooperate with the stopper closing the fuse body for the purpose of applying a flange on the necked spindle against a packing joint on the stopper when the fuse is in the position for transport, the rocking of the lever effecting the withdrawal of said flange from said packing.

The arming of the fuse of the invention is retarded for a certain time after release of the bomb, by means of a clockwork movement, which comprises a spindle connected by a screw connection to one of the firing elements (striker or fuse carrier), said firing member being locked against rotation so that the rotation imparted to the spindle by the clockwork movement effects the gradual unscrewing of the firing member and, finally, its release which causes the arming of the fuse.

In accordance with still a further feature of the invention, the clockwork movement comprises a spiral spring which tends to cause the unscrewing of the aforesaid spindle, on which is keyed a ratchet-wheel meshing with an anchor adapted to pivot around an axis, imparting an oscillating motion to a balance-wheel through the intermediary of a pin carried by the latter.

The speed of rotation of the spindle engaging with the firing element may readily be regulated in the designing, by acting on the force of the spiral spring, as well as on the amplitude of oscillation and moment of inertia of the balance wheel.

Further features and advantages of the invention will become apparent from the following description taken in conjunction with the accompanying drawings which illustrate diagrammatically by way of example, one embodiment thereof, and in which:

Fig, l is an elevation of the fuse, in the position of rest;

Fig. 2 is an axial section of the lower portion of the fuse of Fig. 1;

Fig. 3 is a section along the line 33 of Fig. 2;

Fig. 4 is a section along the line l 3 of Fig. 2;

Fig. 5 is a partial axial section of the upper portion of the fuse, showing the position of the parts during transport with handling;

Fig. 6 shows the parts after suspension of the bomb on the bomb releasing mechanism;

Fig. '7 is a section of the upper part of the fuse, showing the position of the parts once the fuse is armed;

Figs. 8 and 9 show respectively the position of the striker when the fuse is armed and on impact;

Fig. 10 is a section through the line Hll0 of Fig. 7, on a reduced scale; and

Fig. 11 shows a detail.

In the embodiment illustrated, the fuse comprises a body I on which is attached a case 2 containing a clockwork movement.

In a bore 3 in the body l a striker 4 is adapted to slide and this striker 4 serves to strike against a primer 5 fixed in the body I. Between the primer 5 and the striker 4 is interposed a spring 6.

The striker is connected by a screw joint 1 to a spindle 3 of the clockwork movement in the case 2, and it is secured against rotation by a tongue 9 depending from a plate It! (integral with the fuse body I) and engaging in a longitudinal slot H in the striker 4. A spiral spring I2, similar to a watch spring, tends to turn the spindle 8 in a direction such that the striker 4 tends to unscrew itself from the spindle 8 against the action of the spring 6.

The spindle 8 carries a ratchet wheel l3 engaging with a pawl l4 adapted to rock around an axis l5, carrying with it a balance-wheel l8 through the agency of the part E6 of the anchor M and a pin H.

In the position of rest (Fig. 1), the spindle 8 is held by a safety device comprising a pin l5 fixed to a tube 22 and engaging in a slot 2| in the spindle 8.

The tube 20, which is adapted to slide in a tube 2%., forming the upper part of the fuse body, is locked in the position shown in Figs. 5 and 6 by means of a spring 22 bearing, at one end, against a bearing 23 on the tube 20 and, at the other end, against a ring 24 mounted on a locking rod 25. The tube 20, under the action of the spring 22, bears against balls 26, or equivalent locking means, which themselves are supported against the rear face of a sleeve 21 fixed in the tube 2|]. The rod 25 is furnished, at a suitable point, with a neck 28 which, when located opposite the balls 26 (Fig. 7) enables the latter to engage therein, thus releasing the tube 20, which is then able to slide towards the rear over the sleeve 21. Y The rod 25 is furnished with a flange 30, which retains it in the tube 20a, which is closed near its top by a plug 30a furnished with a packing 3512. Upon the plug 300 there is provided a stopper 3% which is fixed at the top of the tube 200..

The safety rod 25 is held in the position shown in Figs. 1, 2 and 7, against the action of the spring 22 by an auxiliary locking member or lever, indicated as a whole by 3|. This lever has two lower limbs 32 (Fig. 11) and two upper limbs 32a which may be used as a handle to operate the lever. The lower limbs bear, on the inside, two cams 32b which are intended to be applied with a tight frictional fit against flats 33 on the rod 25 (Fig. Those cams comprise a lower cylindrical part 320 adapted to engage into a cylindrical cavity 32d of the same diameter provided in the stopper 320 which closes the top of the tube a. At their upper part the cams 321) have tails 32 with cylindrical upper edges having the same diameter as the lower parts 326 but disposed eccentrically'in relation thereto. The tails 32] may fit into cylindrical cavities 322', of corresponding diameter, in the shoulder connecting the upper part of the rod with the flats 33.

The lever 3| preferably has a hole 34 (Fig. 1) in which is engaged a cable or other releasing means enabling it to be disengaged from the rod 25 when the bomb is dropped.

During transport the lever 3| is locked in the position shown in Figs. 1 and 5 by a safety pin or equivalent device 35 which passes through holes 35a (Figs. 6 and 10) of the lever 3| and through a hole 35b of the rod 25. In that position the flange 3B of the rod 25 is pressed against the packing b of the plug 30a. The concave surface 322' of the rod 25 applies against the convex edge 32g of the tail 32f on the cam 325, whereas the lower cylindrical part 320 of said cam rests in the corresponding cavity 32d in the stopper 32c.

The limbs 32a. of the lever are joined by a transverse portion 32m (Fig. 11) adapted to bear against a member of the bomb-releasing mechanism, in order to prevent any untimely disengaging of the lever 32. In Fig. 6, said portion 32m of the lever 3| is shown as bearing against the screw brake 32k of the bomb-releasing mechanism, i. e., against a rod integral with the latter and intended to engage between the screw blades with which certain aerial bomb fuses are equipped, in order to prevent premature rotation.

The fuse operates as follows:

When the bomb is placed in the bomb releasing mechanism the releasable safety cable is hooked into the hole and the safety pin 35 is removed. The lever 3| is then rocked into the position shown in Fig. 6 wherein its upper limbs 32a embrace the screw brake 3270. During the rocking movement of the lever 3| the lower cylindrical part 320 of each cam pivots in the cavity 32d of the stopper 32c. The eccentrical surface 32g on the tail 32 which engages the shoulder 321' of the rod 25 pushes slightly upwards, at the beginning, the rod 25 whereas the flange 30 compresses the packing 301). As soon as the tail 32b escapes the shoulder 322' of the rod 25 that rod is pushed downwards by the spring 22 and comes into the position shown in Fig. 6 Where the shoulder 321' is applied against the cylindrical edge 320 of the cam 321).

When the bomb is to be released, the lever 3| is pulled away after the screw brake 3270 has been shifted aside. The pulling away of the lever causes at the beginning a slight movement of the rod 25 upwards; then the spring 22 pushes the rod 25 downwards, thus bringing the neck 23 opposite the balls 26, which engage therein. The rod 25 is then arrested through its flange 30 encountering a bearing M) on the sleeve 21. The tube 20, being then unlocked, is pushed upwards by its spring 22 and releases the pin l9 from the slot 2| in the spindle B. The clockwork movement is set in motion. The spindle 8 turns, and after a certain time completely unscrews the striker 4, which is then held apart from the primer 5 only by the spring 6. On impact, the striker 4 is precipitated by inertia against the primer 6, which transmits the fire to the detonator and to the charge of the bomb in the usual manner.

It is to be clearly understood that minor changes in the details of construction and arrangement of parts may be made without departing from the scope of the invention as set forth in the appended claims.

I claim:

1. A percussion fuse for aerial bombs, comprising fuse body, a stopper to close the upper end of said fuse body, a packing on the inside of the stopper, a tube adapted to slide endwise in said fuse body, a cross-piece in said tube, a clockwork movement for retarding the arming of the fuse .after the release of the bomb, said clockwork movement comprising a spindle adapted to pivot in the fuse body, two firing elements, a screw connection joining one of the firing elements to said spindle, said cross-piece engaging said spindle to arrest it, means to arrest against rotation the firing member connected to the spindle, means to impart a rotation to said spindle, at least one locking element to lock said tube against movement, a bearing on said tube, a compression spring engaging by one end said bearing to urge the tube against said locking element, a rod adapted to slide in the fuse body, said rod being formed with opposite flats, a ring on said rod, a flange on said rod, said compression spring engaging by its other end said ring on the rod, said rod being formed with a neck and a detachable auxiliary locking member to prevent the displacement of the rod up to the moment of release of the bomb, said auxiliary locking member being adapted to cooperate with the stopper to apply the flange of the rod against the packing when the fuse is in position for transport, and to effect the removal of said flange from the packing when the auxiliary locking member is shifted from its transport position, the compression spring being adapted, after detachment of the auxiliary locking member, to move said rod endwise to bring its neck opposite said locking element to enable it to withdraw into said neck so as to permit the tube to slide, and disengage from the spindle, which may thus be rotated and unscrew itself from the firing member connected thereto, which is finally freed, whereby the fuse is armed.

2. A percussion fuse for aerial bombs, comprising a fuse body, a stopper to close the upper end of said fuse body, a packing on the inside of the stopper, a tube adapted to slide endwise in said fuse body, a cross-piece in said tube, a clockwork movement for retarding the arming of the fuse after the release of the bomb, said clockwork movement comprising a spindle adapted to pivot in the fuse body, two firing elements, a screw connection joining one of the firing elements to said spindle, said cross-piece engaging said spindle to arrest it, means to arrest against rotation the firing member connected tothe spindle, means to impart a rotation to said spindle, at least one locking element to lock said tube against movement, a bearing on said tube, a compression spring engaging by one end said bearing to urge the tube against said locking element, a rod adapted to slide in the fuse body, said rod being formed with opposite flats, a i on said rod, a flange on said rod, said compression spring engaging by its other end said rod which is formed with a neck and a detachable auxiliary locking member to prevent the displacement of the rod up to the moment of release of the bomb, said auxiliary locking member having a lever formed with two limbs, cams on said limbs adapted to be applied with tight frictional fit against the flats on the rod, connecting means to join the cams of the lever with the rod, said connecting means being adapted to permit the lever to be detached from the rod under the action of a determined tensible stress, a transverse part connecting the limbs of the lever, said transverse part being adapted to bear against a member of the bomb releasing mechanism, so as to prevent any premature disengagement of said lever, the cams on said lever being adapted to cooperate with the stopper to apply the flange of the rod against the tight joint of the stopper When the fuse is in position for transport, and to effect the removal of said flange from the packing when the lever is rocked from its transport position, the compression spring being adapted, after detachment of the auxiliary locking memher, to move said rod endwise to bring its neck opposite said locking element to enable it to withdraw into said neck so as to permit the tube to slide, and disengage from the spindle which may thus be rotated and unscrew itself from the firing member connected thereto, which is finally freed, whereby the fuse is armed.

PAUL EMILE JOSEPH DENOIX. 

